Effect of stocking density and diet on growth and survival of post-larvae of the taquilla clam Mulinia edulis cultivated in sand in a hatchery

We determined the effect of stocking density and type of diet on the growth and survival of post-larvae of the taquilla clam Mulinia edulis, as a contribution to the development of technology for the commercial cultivation of this species. Larval cultures of 14 days gave rise to postlarvae which were cultivated in closed systems in sand for 30 days, at densities of 5, 10 and 20 post-larvae cm^-2. To determine the effect of diet, 3 monospecific diets (Isochrysis aff galbana (clone T-ISO), Phaeodactylum tricornotum and Tetraselmis suecica) and 2 mixed diets [I. galbana (clon T-ISO) (50%) – P. tricornotum (50%) and I. galbana (clon T-ISO) (33%) – P. tricornotum (33%) – T. suecica (33%)] were provided at a fixed total ration of 100,000 cell ml^-1 day ^-1. Cultivation at a density of 5 post-larvae cm-2 produced the greatest valve length at age 44 days, 1707 ± 200 mm. Postlarvae fed with Isochrysis galbana (clone T-ISO) had the greatest valve length, 2225 ± 430 mm at age 50 days. The survival of postlarvae was about 50%, and was not affected by the different levels of the parameters analyzed (cultivation density and diet).